Method and apparatus for producing form coke

Abstract

A method of producing form coke that is coke having pieces of substantially identical form using a heated shaft furnace comprises mixing fine coke with a caking coal and pressing the mixture at temperatures at which the mixture is plastic in order to form briquettes. The briquettes are permitted to harden and degasify and thereafter they are exposed to a high temperature after hardening for example to a temperature of from 400° to 900° C from 60 to 120 minutes. Thereafter the briquettes are cooled. A first mixing substance is prepared by permitting a fine coal to fall in a non-compressed stream in the shaft furnace while heat is transferred thereto substantially by radiation.

What is claimed is: 
     
       1. A method of producing form coke pieces having uniformly mutually identical shape, comprising directing a non-compressed stream of fine coal into the top of a shaft furnace and permitting it to fall downwardly therein so as to permit the hot walls of the furnace to radiate heat to the fine coal and at a rate and temperature such that the fine coal is heated within 1 or 2 seconds up to from 800° to 900° C, permitting the fine coal to fall through a height within the shaft furnace to cause the coal particles to become degassed as completely as possible, permitting the fine coal which is formed to accumulate at the bottom of the shaft furnace and regularly withdrawing the accumulated quantities of coal particles and mixing it with caking coal in a mixer in proportions of about two parts of fine coke to one part of caking coal while the fine coke is still hot so that the caking coal becomes partly degassed and forms a mixture with the fine coke, drawing off the carbonization gases at various elevations throughout the shaft furnace and separating the gases drawn at the upper levels which are rich in hydrocarbons from the gases drawn at the lower levels which are richer in hydrogen, collecting the carbonization gases and subjecting them to an after heating in the presence of water and steam so as to convert the hydrocarbons and carbon substantially to carbon monoxide and hydrogen and at the same time to decompose the ammonia gases which are formed to nitrogen and hydrogen with the aid of the water and steam, adding a catalyst such as a nickel carrier catalyst to the carbonization gases, directing the withdrawn carbonization gases through connecting ducts which widen in an obliquely upwardly extending direction so that only a minimum quantity of coal and coke dust is entrained by the carbonization gases withdrawn, and directing the carbonization gases into heatable retorts into which steam and water is supplied, pressing the mixture into a coke briquette, exposing the finished briquette to temperatures of up to 400° for 180 minutes so as to harden the briquettes and increase the mechanical resistance of the coke briquettes, and thereafter exposing the coke briquettes to temperatures of up to 900° C for from 60 to 120 minutes for an after hardening of the coke briquettes during which degasification gases are still produced, and thereafter permitting the coke briquettes to cool, recirculating the decarbonization gases back into the shaft furnace, and cooling the briquettes by circulating inert gases over the briquettes and circulating the inert gases which have been heated by the briquettes in heat exchange relationship with water for heating the water.